This invention relates to a blasting system, to a method of controlling the blasting or initiation of a plurality of detonators in a blasting system, and to a marker for use in a blasting system.
Detonators are often connected to one another in a predetermined sequence and programmed so that each detonator is initiated at a predetermined time relative to other detonators in the sequence. A preset time difference may prevail between adjacent detonators in the sequence but this time difference can be dependent on a geographical or physical pattern in which the detonators are positioned or on geological factors such as the nature of the rock in which the detonators are placed. More generally it can be said that parameters of a blasting system such as a detonator layout or configuration or a timing sequence are influenced by the environment in which the detonators are used. For example in an underground situation particular physical and timing blasting patterns may apply in respect of detonators which are in a stope as opposed to detonators which are in a gully.
A practical difficulty which can arise at least in this connection when a complex blasting pattern is used, or when there are a large number of detonators in a blasting system, is the formulation by a user of a visual depiction of the interconnected detonators in a manner which facilitates the correct implementation of a desired blast sequence. For example at what location must time delays, assigned to the detonators, be changed? Where does a row or branch of detonators start, or finish? Where, in a blast structure, does use start or stop of a particular type or class of detonator? and so on.